Rockwell Automation 6000 PowerFlex Medium Voltage Variable Frequency Drive Installation Instructions - Manual (Page 58)

58 Rockwell Automation Publication 6000-IN006A-EN-P - April 2014
Chapter 4 Drive Electrical Interconnection
Each secondary winding set will have a designated C, B, and A terminal
connection. For example, (from top to bottom and left to right) the terminals
from the first winding set are C1, B1, and A1, the terminals from the next
winding set are C2, B2, and A2, and so on.
As shown in Figure 35 , the first winding set (C1, B1, and A1) will connect to the
three-phase input power connection of the first power module in the U motor
phase array (PCA1), the second winding set will connect to the second power
module in the U motor phase array (PCA2), and the third winding set will
connect to the third power module in the U motor phase array (PCA3). The
next three winding sets connect to the power modules in the V motor phase array.
The remaining three winding sets connect to the power modules in the W motor
phase array.
Figure 35 shows 3/3.3 kV configuration. The 6/6.6 kV and 10 kV configuration
have more power modules and therefore have more corresponding isolation
transformer secondary windings. The concept is the same—the top third of the
winding sets feeds the power modules in the U phase, the middle third feeds the
power modules in the V phase, and the bottom third feeds the power modules in
the W phase.
Each three-phase secondary winding set of the isolation transformer has three
individual single phase power cables connecting its output to the three-phase
power input of its corresponding power module.
For drives with fixed-mounted power modules, the U and W phase
interconnections to the isolation transformer secondary windings are on the
front of the isolation transformer and the connections to the V phase are on the
rear of the isolation transformer. The power cable connections to the power
modules are made at the factory. Therefore, the field power cable connections
need to be made at the isolation transformer secondary winding termination
points (
Figure 37 ).
For drives with drawout power modules, all of the interconnections between the
isolation transformer secondary windings and the power modules are made in the
rear of the isolation transformer and the connection to the power modules are
also in the rear. The power cable connections to the isolation transformer
secondary winding termination point are made at the factory. Therefore, the field
power cable connections must be made at the power module input points
(
Figure 38 ).